3,018 research outputs found
HARLEM IN SHAKESPEARE AND SHAKESPEARE IN HARLEM: THE SONNETS OF CLAUDE MCKAY, COUNTEE CULLEN, LANGSTON HUGHES, AND GWENDOLYN BROOKS
This study responds to the need for an understanding of the relation of form and political critique within the sonnet form, and hopes to demonstrate that the sonnet can be used to effectively articulate the experience of racism, especially the Du Boisian concept of double- consciousness, a sense of two-ness born of being both black and American. The fundamental structure of the sonnet (octave, volta, sestet) is dialectical; it contests the idea it just introduced (Caplan, Poetic Form: An Introduction 75). The sonnet\u27s self-reflexive structure has been adopted and adapted by poets such as McKay, Cullen, Hughes, and Brooks. The formal and social characteristics of sonnets by African-Americans function synergistically: the way that the octave and the sestet respond to each other in a single poem is also similar to the call-and- response movement of African American oral culture. Its tendency to mix two unlike things is like Harlem itself: a compressed space where the street sweeper rubs shoulders with the business tycoon. Perhaps most importantly, the sonnet can be a Trojan horse, a genteel container that conceals a potentially subversive message. This study is constructed around related lines of questioning: First, why did African American poets, in an era usually associated with free verse, choose to adopt a traditional form? Second, how do African American poets adapt a European form as a lens into African American experience? Sonnets by African Americans reflect the complexity of a seemingly simple triangulation between the traditional requirements of form, the promise of equality, and the reality of racism. African American poets infuse Harlem in Shakespeare, pouring black consciousness into the European form, and they raise Shakespeare in Harlem, elevating the status of African American forms to the highest levels of literary art. At the same time, this study demonstrates the value of a prosody-based approach for examining how small formal details contribute substantially to the reader\u27s impression of the sonnet. These poets deploy the rules of the sonnet ingeniously and unexpectedly. Additionally, the sonnet is a way to separate from and simultaneously be a part of the dominant culture by writing a critical message in a recognizable form. Black culture can criticize white culture, while at the same time acknowledging the mutual, inescapable relationship that binds blacks and white Americans together. Additionally, the sonnet is a way to separate from and simultaneously be a part of the dominant culture by writing a critical message in a recognizable form. Black culture can criticize white culture, while at the same time acknowledging the mutual, inescapable relationship that binds blacks and white Americans together
Mesoscopic motion of atomic ions in magnetic fields
We introduce a semiclassical model for moving highly excited atomic ions in a
magnetic field which allows us to describe the mixing of the Landau orbitals of
the center of mass in terms of the electronic excitation and magnetic field.
The extent of quantum energy flow in the ion is investigated and a crossover
from localization to delocalization with increasing center of mass energy is
detected. It turns out that our model of the moving ion in a magnetic field is
closely connected to models for transport in disordered finite-size wires.Comment: 4 pages, 2 figures, subm. to Phys.Rev.A, Rap.Co
Plasmodium falciparum 19-Kilodalton Merozoite Surface Protein 1 (MSP1)-Specific Antibodies That Interfere with Parasite Growth In Vitro Can Inhibit MSP1 Processing, Merozoite Invasion, and Intracellular Parasite Development
Merozoite surface protein 1 (MSP1) is a target for malaria vaccine development. Antibodies to the 19-kDa carboxy-terminal region referred to as MSP1(19) inhibit erythrocyte invasion and parasite growth, with some MSP1-specific antibodies shown to inhibit the proteolytic processing of MSP1 that occurs at invasion. We investigated a series of antibodies purified from rabbits immunized with MSP1(19) and AMA1 recombinant proteins for their ability to inhibit parasite growth, initially looking at MSP1 processing. Although significant inhibition of processing was mediated by several of the antibody samples, there was no clear relationship with overall growth inhibition by the same antibodies. However, no antibody samples inhibited processing but not invasion, suggesting that inhibition of MSP1 processing contributes to but is not the only mechanism of antibody-mediated inhibition of invasion and growth. Examining other mechanisms by which MSP1-specific antibodies inhibit parasite growth, we show that MSP1(19)-specific antibodies are taken up into invaded erythrocytes, where they persist for significant periods and result in delayed intracellular parasite development. This delay may result from antibody interference with coalescence of MSP1(19)-containing vesicles with the food vacuole. Antibodies raised against a modified recombinant MSP1(19) sequence were more efficient at delaying intracellular growth than those to the wild-type protein. We propose that antibodies specific for MSP1(19) can mediate inhibition of parasite growth by at least three mechanisms: inhibition of MSP1 processing, direct inhibition of invasion, and inhibition of parasite development following invasion. The balance between mechanisms may be modulated by modifying the immunogen used to induce the antibodies
Galaxy-scale Star Formation on the Red Sequence: the Continued Growth of S0s and the Quiescence of Ellipticals
This paper examines star formation (SF) in relatively massive, primarily
early-type galaxies (ETGs) at z~0.1. A sample is drawn from bulge-dominated
GALEX/SDSS galaxies on the optical red sequence with strong UV excess and yet
quiescent SDSS spectra. High-resolution far-UV imaging of 27 such ETGs using
HST ACS/SBC reveals structured UV morphology in 93% of the sample, consistent
with low-level ongoing SF (~0.5 Ms/yr). In 3/4 of the sample the SF is extended
on galaxy scales (25-75 kpc), while the rest contains smaller (5-15 kpc) SF
patches in the vicinity of an ETG - presumably gas-rich satellites being
disrupted. Optical imaging reveals that all ETGs with galaxy-scale SF in our
sample have old stellar disks (mostly S0 type). None is classified as a true
elliptical. In our sample, galaxy-scale SF takes the form of UV rings of
varying sizes and morphologies. For the majority of such objects we conclude
that the gas needed to fuel current SF has been accreted from the IGM, probably
in a prolonged, quasi-static manner, leading in some cases to additional disk
buildup. The remaining ETGs with galaxy-scale SF have UV and optical
morphologies consistent with minor merger-driven SF or with the final stages of
SF in fading spirals. Our analysis excludes that all recent SF on the red
sequence resulted from gas-rich mergers. We find further evidence that
galaxy-scale SF is almost exclusively an S0 phenomenon (~20% S0s have SF) by
examining the overall optically red SDSS ETGs. Conclusion is that significant
number of field S0s maintain or resume low-level SF because the preventive
feedback is not in place or is intermittent. True ellipticals, on the other
hand, stay entirely quiescent even in the field.Comment: Accepted for publication in ApJ. Contains color figures, but
compatible with non-color printer
“Dogged” Search of Fresh Nakhla Surfaces Reveals New Alteration Textures
Special Issue: 74th Annual Meeting of the Meteoritical Society, August 8-12, 2011, London, U.K.International audienceCarbonaceous chondrites are considered as amongst the most primitive Solar System samples available. One of their primitive characteristics is their enrichment in volatile elements.This includes hydrogen, which is present in hydrated and hydroxylated minerals. More precisely, the mineralogy is expected to be dominated by phyllosilicates in the case of CM chondrites, and by Montmorillonite type clays in the case of CI. Here, in order to characterize and quantify the abundance of lowtemperature minerals in carbonaceous chondrites, we performed thermogravimetric analysis of matrix fragments of Tagish Lake, Murchison and Orgueil
The Dipion Mass Spectrum In e+e- Annihilation and tau Decay: A Dynamical (rho0, omega, phi) Mixing Approach
We readdress the problem of finding a simultaneous description of the pion
form factor data in e+e- annihilations and in tau decays. For this purpose, we
work in the framework of the Hidden Local Symmetry (HLS) Lagrangian and modify
the vector meson mass term by including the pion and kaon loop contributions.
This leads us to define the physical rho, omega and phi fields as linear
combinations of their ideal partners, with coefficients being meromorphic
functions of s, the square of the 4--momentum flowing into the vector meson
lines. This allows us to define a dynamical, i.e. s-dependent, vector meson
mixing scheme. The model is overconstrained by extending the framework in order
to include the description of all meson radiative (V P gamma and P gamma gamma
couplings) and leptonic (Ve+e- couplings) decays and also the isospin breaking
(omega/ phi --> pi+ pi-) decay modes. The model provides a simultaneous,
consistent and good description of the e+e- and tau dipion spectra. The
expression for pion form factor in the latter case is derived from those in the
former case by switching off the isospin breaking effects specific to e+e- and
switching on those for tau decays. Besides, the model also provides a good
account of all decay modes of the form V P gamma, Pgamma gamma as well as the
isospin breaking decay modes. It leads us to propose new reference values for
the rho^0 --> e+ e- and omega --> pi+ pi- partial widths which are part of our
description of the pion form factor. Other topics (phi --> K anti K, the rho
meson mass and width parameters) are briefly discussed. Therefore, we confirm
the 3.3 sigma discrepancy between the theoretical estimate of a_mu based on
e+e- and its direct BNL measurement.Comment: 71 pages, 8 figures. Accepted by EPJ C. Version 3: correct minor
typos, minor changes spread out into the text. Extension of Sections 12.2 and
12.3.5 and introduction of the new Appendix
Hadron Energy Reconstruction for the ATLAS Calorimetry in the Framework of the Non-parametrical Method
This paper discusses hadron energy reconstruction for the ATLAS barrel
prototype combined calorimeter (consisting of a lead-liquid argon
electromagnetic part and an iron-scintillator hadronic part) in the framework
of the non-parametrical method. The non-parametrical method utilizes only the
known ratios and the electron calibration constants and does not require
the determination of any parameters by a minimization technique. Thus, this
technique lends itself to an easy use in a first level trigger. The
reconstructed mean values of the hadron energies are within of the
true values and the fractional energy resolution is . The value of the ratio
obtained for the electromagnetic compartment of the combined calorimeter is
and agrees with the prediction that for this
electromagnetic calorimeter. Results of a study of the longitudinal hadronic
shower development are also presented. The data have been taken in the H8 beam
line of the CERN SPS using pions of energies from 10 to 300 GeV.Comment: 33 pages, 13 figures, Will be published in NIM
Systematic study of charged-pion and kaon femtoscopy in AuAu collisions at =200 GeV
We present a systematic study of charged pion and kaon interferometry in
AuAu collisions at =200 GeV. The kaon mean source radii
are found to be larger than pion radii in the outward and longitudinal
directions for the same transverse mass; this difference increases for more
central collisions. The azimuthal-angle dependence of the radii was measured
with respect to the second-order event plane and similar oscillations of the
source radii were found for pions and kaons. Hydrodynamic models qualitatively
describe the similar oscillations of the mean source radii for pions and kaons,
but they do not fully describe the transverse-mass dependence of the
oscillations.Comment: 499 authors, 27 pages, 13 figures, and 11 tables. v2 is the version
accepted for publication in Phys. Rev. C. Plain text data tables for the
points plotted in figures for this and previous PHENIX publications are (or
will be) publicly available at http://www.phenix.bnl.gov/papers.htm
Medium modification of jet fragmentation in Au+Au collisions at sqrt(s_NN)=200 GeV measured in direct photon-hadron correlations
The jet fragmentation function is measured with direct photon-hadron
correlations in p+p and Au+Au collisions at sqrt(s_NN)=200 GeV. The p_T of the
photon is an excellent approximation to the initial p_T of the jet and the
ratio z_T=p_T^h/p_T^\gamma is used as a proxy for the jet fragmentation
function. A statistical subtraction is used to extract the direct photon-hadron
yields in Au+Au collisions while a photon isolation cut is applied in p+p. I_
AA, the ratio of jet fragment yield in Au+Au to that in p+p, indicates
modification of the jet fragmentation function. Suppression, most likely due to
energy loss in the medium, is seen at high z_T. The fragment yield at low z_T
is enhanced at large angles. Such a trend is expected from redistribution of
the lost energy into increased production of low-momentum particles.Comment: 562 authors, 70 insitutions, 8 pages, and 3 figures. Submitted to
Phys. Rev. Lett. v2 has minor changes to improve clarity. Plain text data
tables for the points plotted in figures for this and previous PHENIX
publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
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